In addition, for tiny hard disk surface damage, some hard disk tools ( such as Data Lifeguard Tools of Western Digital) can fix errors by re-directing to a good sector.
Physical bad sectors can be repaired with hard disk tools ( hard disk check and repair software provided by disk manufacturers). This can't be repaired.īut when outside influence causes data writing error, OS will judge this as physical bad sector. Physical damage of hard disk surface belongs to external physical bad sectors. It can be divided into internal and external physical bad sectors. But what if CHKDSK deletes your important data? You are advised to use MiniTool Power Data Recovery to recover data after CHKDSK.įor physical bad sectors, it has catastrophic damage to hard drive. The CHKDSK command is able to check the disk surface for bad sectors and mark them.
This is called the cause of logical bad sectors.
If ECC correction code calculated by original bytes is different from that calculated by read-out bytes, this will cause ECC error. And all these bytes will be verified and encoded by using ECC. But actually, additional dozens of bytes will be written in hard disk. Generally, 512 bytes need to be written in OS. From the perspective of process, it refers to when data are written in hard disk, it will use ECC logic to re-combine data. It refers to that hard disk is interfered when data are written in it. Logical bad sectors are easier to deal with than physical bad sectors. In general, bad sectors are divided into physical bad sectors and logical bad sectors. In the second case, what type of bed sectors need low-level format? Let's take a look at types of hard disk bad sectors before describing this critical question. For average users, there is no need to consider this matter. In the first case, we don't need to describe in details, because HDD low-level format before it leaves factory only comes into contact with disk engineers. The other is that when hard disk has bad sectors, performing low-level format to it can reduce spreading speed of bad sectors or shield bad sectors. One is that hard disk manufacturers will perform low-level format to disk before it leaves the factory.
So, in general, we had better avoid performing HDD low-level format if it's not very necessary to do so.īut, there are two situations in which we have to carry out low-level format. Data previously saved on hard disk will be lost after low-level format. But the premise is that hard disk isn't physically damaged.įunction of low-level format to HDD: low-level format to HDD is a way to thoroughly initialize disk. People can re-divide sectors by low-level format when large numbers of bad sectors appear, because hard disk has been used for a long time or is affected by external strong magnetic and magnetic field. Many hard disk manufacturers suggest that users try not to perform low-level format. However, performing low-level format on hard disk, which was produced in recent one or two years, has smaller impact on service life of hard disk, because this doesn't belong to physical operation. It has a negative impact on the service life of hard disk. Users should pay attention to the fact that under the previous disk reading technical level, low-level format is a deteriorating operation. Therefore, users don't need to carry out low-level format.Īfter reading this post – Check Out This Way To Recover Files From Formatted Hard Drive, you’ll know what low-level format & high-level format are respectively and the way to recover files from a formatted hard drive. When each disk leaves the factory, hard disk manufacturers have performed low-level format on it. Low-level format only support one hard disk rather than a separate partition.
It can not only be achieved in DOS environment, but also in Windows NT systems. We can see that low-level format is carried out before high-level format. Next, each sector is divided into ID, GAP, DATA and so on. Then, cylinders are divided into several sectors. Low-level format refers to dividing cylinders and tracks in blank disk.